title: Determination of α-tocopherol in vegetable oils using a molecularly imprinted polymers-surface-enhanced Raman spectroscopic biosensor.
abstract: We report the development of a novel hybrid "capture-detection" molecularly imprinted polymers-surface-enhanced Raman spectroscopic (MIPs-SERS) biosensor for the detection and quantification of α-tocopherol (α-Toc) in vegetable oils. α-Toc served as the template for MIPs synthesis. Methacrylic acid formed as the functional monomer. Ethylene glycol dimethacrylate was the cross-linking agent, and 2,2'-azobisisobutyronitrile was used as the initiator. The synthesized MIPs functioned to rapidly and selectively adsorb and separate α-Toc from oil components. We validated a dendritic silver nanostructure synthesized by a displacement reaction to be a suitable SERS substrate for the enhancement of Raman signals. Second-derivative transformations and chemometric models based upon SERS spectral features confirmed the possibility of a rapid and precise detection and quantification of different spiking levels of α-Toc in four different sources of vegetable oils (Mahalanobis distance from 15.93 to 34.01 for PCA model; R > 0.92, RMSE < 0.41 for PLSR model). The MIPs-SERS biosensor had a high sensitivity as well as a good recovery for α-Toc analysis in vegetable oils. The entire analysis required 15 min or less to complete with limited sample preparation.
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Tianjin University of Science and Technology , Tianjin 300457, China.
authors.forename: Shaolong
authors.initials: S
authors.lastname: Feng
authors.forename: Fang
authors.initials: F
authors.lastname: Gao
authors.forename: Zhiwen
authors.initials: Z
authors.lastname: Chen
authors.forename: Edward
authors.initials: E
authors.lastname: Grant
authors.forename: David D
authors.initials: DD
authors.lastname: Kitts
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Lu
mesh_terms: D054802:Molecular Imprinting; D010938:Plant Oils / Q000032:analysis*; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000295:instrumentation / Q000379:methods*; D024502:alpha-Tocopherol / Q000032:analysis*
chemical_list: D010938:Plant Oils; D011108:Polymers; D024502:alpha-Tocopherol